Hi Dayna,
First off, welcome to the site and congrats on you new baby. As far as weight training goes, you want to train your whole body. I would suggest doing up to 3 full body workouts a week to get you going. As far as losing fat, your diet is key there. What you eat plays a major role in reducing overall bodyfat. You can do exercises for a certain bodypart, but that doesn't mean the fat will "go away" from that bodypart. Unfortunately it is not that easy. Eat 5-6 smaller meals a day, each containing a protein and a carb. Drinks lot of water. Weight train, adding muscle to your body will make it more efficient at burning fat. Do not train the same bodypart for at least 48 hours. Get enough sleep. Well there are a few things that will help you achieve your goals.